U.S. patent number 11,135,623 [Application Number 15/836,132] was granted by the patent office on 2021-10-05 for wafer transport container interior atmosphere measurement device, wafer transport container, wafer transport container interior cleaning device, and wafer transport container interior cleaning method.
This patent grant is currently assigned to TDK CORPORATION. The grantee listed for this patent is TDK CORPORATION. Invention is credited to Tatsuhiro Kotsugai, Mutsuo Sasaki.
United States Patent |
11,135,623 |
Sasaki , et al. |
October 5, 2021 |
Wafer transport container interior atmosphere measurement device,
wafer transport container, wafer transport container interior
cleaning device, and wafer transport container interior cleaning
method
Abstract
A wafer transport container interior atmosphere measurement
device is arranged in wafer transport container. The device detects
an atmosphere in the wafer transport container and communicates the
atmosphere. The device includes a detector, a transmitter, and a
power source. The detector detects the atmosphere in the wafer
transport container. The transmitter wirelessly transmits a first
information including a detection result by the detector to an
external receiver. The power source supplies electric power to the
detector and the transmitter.
Inventors: |
Sasaki; Mutsuo (Tokyo,
JP), Kotsugai; Tatsuhiro (Tokyo, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
TDK CORPORATION |
Tokyo |
N/A |
JP |
|
|
Assignee: |
TDK CORPORATION (Tokyo,
JP)
|
Family
ID: |
1000005844885 |
Appl.
No.: |
15/836,132 |
Filed: |
December 8, 2017 |
Prior Publication Data
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|
|
Document
Identifier |
Publication Date |
|
US 20180161830 A1 |
Jun 14, 2018 |
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Foreign Application Priority Data
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|
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Dec 13, 2016 [JP] |
|
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JP2016-241489 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L
21/6734 (20130101); H01L 21/67294 (20130101); B65D
85/30 (20130101); H01L 21/67393 (20130101); H01L
21/304 (20130101); H01L 21/67253 (20130101); H01L
21/68 (20130101); B08B 5/00 (20130101); H01L
21/67775 (20130101) |
Current International
Class: |
B65D
85/30 (20060101); B08B 5/00 (20060101); H01L
21/68 (20060101); H01L 21/677 (20060101); H01L
21/67 (20060101); H01L 21/673 (20060101); H01L
21/304 (20060101) |
Field of
Search: |
;206/710,711 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
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101140635 |
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Mar 2008 |
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CN |
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2002-261159 |
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Sep 2002 |
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JP |
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2003-347397 |
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Dec 2003 |
|
JP |
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2005-202933 |
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Jul 2005 |
|
JP |
|
2014-195230 |
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Oct 2014 |
|
JP |
|
10-2004-0075896 |
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Aug 2004 |
|
KR |
|
10-2011-0103830 |
|
Sep 2011 |
|
KR |
|
10-2014-0047099 |
|
Apr 2014 |
|
KR |
|
Primary Examiner: Ackun; Jacob K
Attorney, Agent or Firm: Oliff PLC
Claims
What is claimed is:
1. A wafer transport container interior atmosphere measurement
device arranged in a wafer transport container and configured to
detect an atmosphere in the wafer transport container and
communicate the atmosphere, the device comprising: a detector
configured to detect the atmosphere in the wafer transport
container; a transmitter configured to wirelessly transmit a first
information including a detection result by the detector to an
external receiver; and a power source configured to supply electric
power to the detector and the transmitter, wherein the power source
comprises: a rechargeable electricity storage unit; and a power
receiving unit that has a non-contact charging power receiving coil
which is configured to (1) receive energy supplied from an outside
power supply through a wall of the container without being directly
connected to the power supply and without opening the container and
(2) charge the electricity storage unit, wherein the non-contact
charging power receiving coil of the power receiving unit is
provided on a bottom portion of the wafer transport container.
2. The wafer transport container interior atmosphere measurement
device according to claim 1, wherein the transmitter is configured
to wirelessly transmit a second information different from the
first information to the receiver when a voltage of the electricity
storage unit becomes a predetermined value or more.
3. The wafer transport container interior atmosphere measurement
device according to claim 1, further comprising a cover portion
configured to cover the detector excluding a sensing portion in
contact with the atmosphere in the wafer transport container, the
transmitter, and the power source so as to avoid contact with the
atmosphere.
4. The wafer transport container interior atmosphere measurement
device according to claim 2, further comprising a cover portion
configured to cover the detector excluding a sensing portion in
contact with the atmosphere in the wafer transport container, the
transmitter, and the power source so as to avoid contact with the
atmosphere.
5. A wafer transport container comprising: the wafer transport
container interior atmosphere measurement device according to claim
1; a housing portion accommodating a wafer and provided with a main
opening for unloading and loading the wafer; and a lid detachably
provided at the main opening, wherein a bottom opening capable of
discharging gas from the wafer transport container is formed at a
bottom portion of the housing portion, and the detector of the
wafer transport container interior atmosphere measurement device is
provided in a vicinity of the bottom opening.
6. A wafer transport container comprising: the wafer transport
container interior atmosphere measurement device according to claim
2; a housing portion accommodating a wafer and provided with a main
opening for unloading and loading the wafer; and a lid detachably
provided at the main opening, wherein a bottom opening capable of
discharging gas from the wafer transport container is formed at a
bottom portion of the housing portion, and the detector of the
wafer transport container interior atmosphere measurement device is
provided in a vicinity of the bottom opening.
7. The wafer transport container interior atmosphere measurement
device according to claim 1, wherein the detector is located at a
wall of the wafer transport container that includes an inlet for
cleaning gas.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a wafer transport container
interior atmosphere measurement device or so that detects an
atmosphere in a wafer transport container for transporting a
wafer.
2. Description of the Related Art
For example, in a semiconductor manufacturing process, wafers are
transported among processing devices using a transport container
called a SMIF, a FOUP, or the like.
To protect a wafer surface from oxidation and contamination, an
environment in a transport container housing wafers is preferably
kept in an inactive state above a predetermined level and kept
having cleanliness above a predetermined level. As a method for
improving an inactive state and the cleanliness of gas in a
transport container, a technique, such as gas purging, of
introducing cleaning gas into the container or a space
communicating with the container has been proposed. In addition, as
a technique of cleaning the interior of a transport container to a
predetermined level, a technique of connecting a pipe to the
container, causing gas in the container to circulate between the
container and an external environmental control unit, and
controlling the concentration of water and the concentration of
oxygen in the container has been proposed (see Patent Document
1).
Patent Document 1: JP 2003-347397 A
SUMMARY OF THE INVENTION
In a conventional method that performs control by leading gas in a
container outside, however, cleanliness in the container cannot be
detected unless gas in the container is once led outside. For this
reason, a process of leading gas in the container outside is
necessary for detection of cleanliness in a container regardless of
whether the container is a container with sufficiently high
cleanliness or a container with low cleanliness. Due to the
disadvantage, streamlining of processing is desired. In addition,
downsizing is difficult in a conventional technique that requires a
pipe for leading gas in a container outside. Gas in a container may
be mixed with different gas while being led outside. The
conventional technique also suffers from a problem with detection
accuracy.
The present invention has been achieved under such circumstances.
It is an object of the invention to provide a wafer transport
container interior atmosphere measurement device that is
downsizable and detects an atmosphere in a wafer transport
container with high accuracy and communicates the atmosphere.
To achieve the above object, the wafer transport container interior
atmosphere measurement device according to the present invention is
a wafer transport container interior atmosphere measurement device
arranged in a wafer transport container and configured to detect an
atmosphere in the wafer transport container and communicate the
atmosphere, the device comprising:
a detector configured to detect the atmosphere in the wafer
transport container;
a transmitter configured to wirelessly transmit a first information
including a detection result by the detector to an external
receiver; and
a power source configured to supply electric power to the detector
and the transmitter.
Since the wafer transport container interior atmosphere measurement
device according to the present invention is arranged in the wafer
transport container, the atmosphere in the wafer transport
container can be detected even without leading gas in the wafer
transport container to outside the wafer transport container. Since
the wafer transport container interior atmosphere measurement
device comprises the transmitter configured to wirelessly
communicate the detection result, the receiver located away from
the wafer transport container being transported in a factory can
recognize the detection result of the atmosphere in the wafer
transport container, and an appropriate processing, such as
cleaning processing, can be carried out against the wafer transport
container based on the detection result as needed. Since data is
transmitted through wireless communication, an electrical contact
for data transmission need not be provided on the surfaces of the
wafer transport container interior atmosphere measurement device
and the wafer transport container installing the wafer transport
container interior atmosphere measurement device, and the
airtightness and durability of the wafer transport container are
little impaired.
For example, the power source may comprise:
a rechargeable electricity storage unit; and
a power receiving unit configured to receive energy supply from an
outside and charge the electricity storage unit.
When the power source comprises the electricity storage unit and
the power receiving unit, the electricity storage unit is charged
at appropriate timing, and the wafer transport container interior
atmosphere measurement device can thereby continuously detect the
atmosphere in the wafer transport container and communicate the
detection result without battery replacement and the like. Thus,
the above-mentioned wafer transport container interior atmosphere
measurement device can save much trouble in battery life management
and can reduce battery management and replacement costs.
For example, the power receiving unit may comprise a non-contact
charging power receiving coil.
When the power receiving unit comprises the non-contact charging
power receiving coil, the above-mentioned wafer transport container
interior atmosphere measurement device can charge the electricity
storage unit even without a wiring that is electrically conductive
with the outside. For this reason, although a measurement device
which is an electrical device is installed as the wafer transport
container interior atmosphere measurement device, the wafer
transport container interior atmosphere measurement device little
impairs the airtightness and durability of the wafer transport
container, where the wafer transport container interior atmosphere
measurement device is installed.
For example, the transmitter may wirelessly transmit a second
information different from the first information to the receiver
when a voltage of the electricity storage unit becomes a
predetermined value or more.
When the transmitter transmits the second information associated
with the voltage of the electricity storage unit to the receiver,
the receiver can recognize whether the wafer transport container
interior atmosphere measurement device of interest is in a state
capable of detecting the atmosphere in the wafer transport
container and communicating the atmosphere. With this
configuration, even if the voltage of the electricity storage unit
becomes less than the predetermined value while the wafer transport
container interior atmosphere measurement device is transported
together with the wafer transport container, when the voltage
recovers to the predetermined value or more by charging the
electricity storage unit via the power receiving unit, the receiver
recognizes the recovery by receiving the second information, and
the wafer transport container interior atmosphere measurement
device can be caused to detect the atmosphere in the wafer
transport container and communicate the atmosphere at appropriate
timing.
For example, the wafer transport container interior atmosphere
measurement device according to the present invention may further
comprise a cover portion configured to cover the detector excluding
a sensing portion in contact with the atmosphere in the wafer
transport container, the transmitter, and the power source so as to
avoid contact with the atmosphere.
The wafer transport container interior atmosphere measurement
device including the above-mentioned cover portion can protect
circuits, electronic parts, and the like constituting the detector,
the transmitter, and the power source from outgas of a wafer and
has preferable reliability.
The wafer transport container according to the present invention
may comprise:
any of the above-mentioned water transport container interior
atmosphere measurement devices.
a housing portion accommodating a wafer and provided with a main
opening for unloading and loading the wafer; and
a lid detachably provided at the main opening,
wherein a bottom opening capable of discharging gas from the wafer
transport container is formed at a bottom portion of the housing
portion, and
the detector of the wafer transport container interior atmosphere
measurement device is provided in a vicinity of the bottom
opening.
In the above-mentioned wafer transport container, the detector can
appropriately detect the atmosphere in the wafer transport
container.
The wafer transport container interior cleaning device according to
the present invention is a wafer transport container interior
cleaning device for cleaning an interior of a wafer transport
container, the device comprising:
a cleaning gas inlet configured to introduce a cleaning gas into
the wafer transport container;
a receiver configured to receive a first information including a
detection result of an atmosphere in the wafer transport container
from a wafer transport container interior atmosphere measurement
device arranged in the wafer transport container; and
a controller configured to control the cleaning gas inlet based on
the detection result received by the receiver.
In the wafer transport container interior cleaning device according
to the present invention, the cleaning gas inlet is controlled
based on the first information including the detection result by
the wafer transport container interior atmosphere measurement
device, and the cleaning processing can be thereby efficiently
carried out in a short time. In addition, if cleanliness in the
wafer transport container is sufficiently high, the cleaning
processing can be omitted or simplified.
A wafer transport container interior cleaning method according to
the present invention, comprising the steps of:
detecting an atmosphere in a wafer transport container by a wafer
transport container interior atmosphere measurement device arranged
in the wafer transport container;
wirelessly transmitting a first information including a detection
result of the atmosphere by the wafer transport container interior
atmosphere measurement device;
receiving the first information by a receiver of a wafer transport
container interior cleaning device; and
controlling a cleaning gas inlet of the wafer transport container
interior cleaning device based on the detection result included in
the first information received by the receiver and cleaning an
interior of the wafer transport container by a controller of the
wafer transport container interior cleaning device.
In the wafer transport container interior cleaning device according
to the present invention, the cleaning gas inlet is controlled
based on the first information including the detection result by
the wafer transport container interior atmosphere measurement
device, and the cleaning processing can be thereby efficiently
carried out in a short time. In addition, if cleanliness in the
wafer transport container is sufficiently high, the cleaning
processing can be omitted or simplified.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a wafer transport container and a
wafer transport container interior cleaning device according to an
embodiment of the present invention;
FIG. 2 is a perspective view showing the interior of a housing
portion of the wafer transport container shown in FIG. 1;
FIG. 3 is a schematic perspective view of a wafer transport
container interior atmosphere measurement device according to the
embodiment of the present invention;
FIG. 4 is a conceptual diagram showing a schematic circuit
configuration of the wafer transport container interior atmosphere
measurement device shown in FIG. 3;
FIG. 5 is a schematic perspective view showing a vicinity of an
installation stand of the wafer transport container interior
cleaning device shown in FIG. 1;
FIG. 6 is a conceptual view for explaining communication between
the wafer transport container interior atmosphere measurement
device and the wafer transport container interior cleaning device
shown in FIG. 1;
FIG. 7 is a conceptual view showing a state during a wafer
transport container interior cleaning process of cleaning the
interior of the wafer transport container shown in FIG. 1;
FIG. 8 is a conceptual view showing another state during the wafer
transport container interior cleaning process of cleaning the
interior of the wafer transport container shown in FIG. 1;
FIG. 9 is a conceptual view showing a state during a wafer
transport container interior cleaning process of cleaning the
interior of a wafer transport container according to a first
modification;
FIG. 10 is a conceptual view showing a state during a wafer
transport container interior cleaning process of cleaning the
interior of a wafer transport container according to a second
modification; and
FIG. 11 is a flowchart representing a wafer transport container
interior cleaning process according to the embodiment of the
present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is described below based on an embodiment
shown in drawings.
FIG. 1 is a schematic view representing a FOUP 20 as a wafer
transport container and a load port device 40 as a wafer transport
container interior cleaning device according to an embodiment of
the present invention. The FOUP 20 includes a wafer transport
container interior atmosphere measurement device 30 (hereinafter
simply referred to as a measurement device 30). The load port
device 40 cleans the FOUP 20.
The load port device 40 constitutes a part of an EFEM 60 for taking
a wafer 10 out of the FOUP 20 and transporting the wafer 10 to a
semiconductor processing device (not shown). The load port device
40 is installed on a wall portion 64 of a wafer transport chamber
66 formed in the EFEM 60 and functions as a part of an interface
for moving the wafer 10 to a semiconductor treatment chamber. The
interior of the wafer transport chamber 66 of the EFEM 60 is
maintained in a fixed clean environment using a fan filter unit or
the like. The wafer transport chamber 66 is provided with a
transport robot 62 or so including a robot arm for taking the wafer
10 from the FOUP 20.
The load port device 40 includes an installation stand 46 on which
the FOUP 20 is to be installed. The FOUP 20 for hermetically
storing and transporting the wafers 10 can be detachably mounted on
an upper portion of the installation stand 46 in the Z-axis
direction. The installation stand 46 can move from a position shown
in FIG. 5 to a position shown in FIG. 1 in the Y-axis direction
while the FOUP 20 is mounted on the upper portion. Incidentally, in
the drawings, the Y-axis is a movement direction of the
installation stand 46, the Z-axis is a vertical direction, and the
X-axis is a vertical direction to the Y-axis and the Z-axis.
The load port device 40 shown in FIG. 1 includes a door 47 for
opening a lid 26 of the FOUP 20. The load port device 40 opens the
lid 26 of the FOUP 20 using the door 47 after moving the FOUP 20 to
a position where the FOUP 20 engages with an opening in the wall
portion 64. With this operation, the interior of a housing portion
22 of the FOUP 20 and the wafer transport chamber 66 can be
airtightly linked via a main opening 22a of the housing portion
22.
The load port device 40 shown in FIG. 1 also functions as a wafer
transport container interior cleaning device that cleans the
interior of the FOUP 20 as a wafer transport container. The load
port device 40 includes a front purge nozzle 41 and a bottom purge
nozzle 42. The front purge nozzle 41 serves as a cleaning gas inlet
where cleaning gas is introduced into the FOUP 20. The front purge
nozzle 41 is arranged in the vicinity of the main opening 22a
linked to the wafer transport chamber 66. The front purge nozzle 41
emits cleaning gas toward the main opening 22a of the FOUP 20 and
introduces the cleaning gas into the FOUP 20. Incidentally, any
gas, such as inactive gas of nitrogen gas or so and dry air, may be
used as a cleaning gas for cleaning the interior of the FOUP 20,
but nitrogen gas is preferably used.
The bottom purge nozzle 42 protrudes from the installation stand 46
and is linked to bottom openings 23a and 23b which are formed in a
bottom portion 22b of the housing portion 22 of the FOUP 20. The
bottom purge nozzle 42 includes an introduction nozzle 42a and a
discharge nozzle 42b. The introduction nozzle 42a is linked to the
bottom opening 23a provided at a position farther away from the
main opening 22a than a central position of the bottom portion 22b.
The discharge nozzle 42b is linked to the bottom opening 23b
provided at a position closer to the main opening 22a than the
central position of the bottom portion 22b. The introduction nozzle
42a can emit cleaning gas, and the cleaning gas emitted from the
introduction nozzle 42a is introduced into the FOUP 20 via the
bottom opening 23a. An atmosphere in the FOUP 20 can be efficiently
cleaned by discharging gas in the FOUP 20 via the discharge nozzle
42b simultaneously with emission of cleaning gas from the
introduction nozzle 42a.
Introduction of cleaning gas through the front purge nozzle 41 and
the introduction nozzle 42a of the bottom purge nozzle 42 is
controlled by a controller 43 of the load port device 40. The
controller 43 controls introduction of cleaning gas into the FOUP
20 by, for example, opening and closing an electromagnetic valve
provided in piping that supplies cleaning gas to the front purge
nozzle 41 and the introduction nozzle 42a. The controller 43 may
control introduction of cleaning gas into the FOUP 20 by adjusting
the discharge amount from the discharge nozzle 42b of the bottom
purge nozzle 42. Incidentally, gas in the FOUP 20 may be discharged
through the discharge nozzle 42b by forced exhaust or natural
exhaust.
The load port device 40 includes a receiver 44. The receiver 44
receives a first information, a second information, and the like
from the measurement device 30 arranged in the FOUP 20. The first
information includes a detection result of the atmosphere in the
FOUP 20. The second information is transmitted when a voltage of an
electricity storage unit 34 (see FIG. 4) in the measurement device
30 becomes a predetermined value or more. The receiver 44 includes
a modem or so and can communicate with at least a transmitter 32
(see FIG. 4) of the measurement device 30 provided in the FOUP 20
being mounted on the installation stand 46. As mentioned below, the
receiver 44 can transmit various types of signals including a
control signal to the transmitter 32. The controller 43 can control
the front purge nozzle 41 and the bottom purge nozzle 42 and clean
the interior of the FOUP 20 based on a detection result included in
the first information received by the receiver 44. The receiver 44
and a method for cleaning the interior of the FOUP 20 using
information obtained via the receiver 44 is described below in
detail.
The FOUP 20 mounted on the installation stand 46 of the load port
device 40 in FIG. 1 is a transport container for transporting the
wafer 10 in a semiconductor factory. The FOUP 20 has a box outer
shape (generally rectangular parallelepiped), and a space for
accommodating the wafer 10 inside is formed in the FOUP 20.
The FOUP 20 includes the housing portion 22 and the lid 26 that is
detachable from the housing portion 22. The housing portion 22
accommodates the wafer 10, and the main opening 22a for unloading
the wafer 10 from the interior of the FOUP 20 and loading the wafer
10 into the FOUP 20 is formed in a side surface of the housing
portion 22. As shown in FIG. 2, shelves for placing a plurality of
horizontally held wafers 10 in the vertical direction are arranged
in the housing portion 22. The wafers 10 mounted on the shelves are
housed at fixed intervals in the FOUP 20.
As shown in FIG. 1, the lid 26 is provided detachably from the main
opening 22a of the housing portion 22. The load port device 40 can
open the main opening 22a of the FOUP 20 by engaging the door 47
with the lid 26 and moving the door 47 engaged with the lid 26 into
the wafer transport chamber 66.
As shown in FIG. 1 and FIG. 2, four bottom openings 23a and 23b are
formed in total in the bottom portion 22b of the housing portion 22
of the FOUP 20. The introduction nozzles 42a of the load port
device 40 are linked to two bottom openings 23a provided at
positions farther away from the main opening 22a than the central
position of the bottom portion 22b, and cleaning gas is introduced
into the FOUP 20 via the bottom openings 23a. The discharge nozzles
42b of the load port device 40 are linked to two bottom openings
23b provided at positions closer to the main opening 22a than the
central position of the bottom portion 22b, and gas is discharged
from the FOUP 20 via the bottom openings 23b.
As shown in FIG. 1, the measurement device 30, which detects the
atmosphere in the FOUP 20 and communicates the atmosphere, is
provided on the bottom portion 22b of the housing portion 22 of the
FOUP 20. As shown in FIG. 2, the measurement device 30 (a detector
31 (see FIG. 4) in the measurement device 30 in particular) is
provided in the vicinity of the two bottom openings 23b provided at
the positions closer to the main opening 22a, but the measurement
device 30 is arranged at any position.
As shown in FIG. 3, the measurement device 30 has a generally
rectangular parallelepiped outer shape whose surface is mostly
covered with a cover portion 38, such as a resin. The measurement
device 30 has a cartridge shape where the detector 31, the
transmitter 32, a power source 33, a communication controller 36
(see FIG. 4), and the cover portion 38 mentioned below are
integrated, and is detachable from the FOUP 20. Since the
measurement device 30 has a detachable cartridge shape, the
measurement device 30 can be removed at the time of, e.g., cleaning
of the FOUP 20, and the measurement device 30 can be attached to
another FOUP 20 and used as needed. Incidentally, the measurement
device 30 are not limited to having the above-mentioned shape and
structure, and may be installed undetachably from the FOUP 20.
FIG. 4 is a conceptual diagram showing a schematic circuit
configuration of the measurement device 30. The measurement device
30 includes the detector 31, the transmitter 32, the power source
33, and the communication controller 36. The detector 31 detects
the atmosphere in the FOUP 20. The transmitter 32 wirelessly
transmits a first information including a detection result by the
detector 31 to the receiver 44 of the load port device 40. The
power source 33 supplies power to the detector 31 and the
transmitter 32. The communication controller 36 controls the
constituent parts of the measurement device 30.
The detector 31 shown in FIG. 4 includes a sensor that detects the
atmosphere in the FOUP 20, such as components of gas in the FOUP 20
and the cleanliness of the gas (the amount of particles included in
the gas). Any sensor that detects cleanliness, such as an oxygen
concentration meter, a water (vapor) concentration meter, a
nitrogen concentration meter, a differential pressure gauge, and a
particle counter, may be included in the detector 31. As shown in
FIG. 3, the detector 31 includes a sensing portion 31a. The sensing
portion 31a is exposed from the cover portion 38 and is in contact
with the atmosphere in the FOUP 20. The detector 31 detects the
cleanliness of gas via the sensing portion 31a.
The transmitter 32 shown in FIG. 4 wirelessly transmits the first
information including a detection result of the atmosphere in the
FOUP 20, the second information transmitted when a voltage of the
electricity storage unit 34 in the measurement device 30 becomes a
predetermined value or more, and the like to the receiver 44 of the
load port device 40. The transmitter 32 can receive a control
signal about the measurement device 30 from the receiver 44.
Although the transmitter 32 is composed of a modem, an antenna, and
the like, but a specific configuration of the transmitter 32 is not
particularly limited.
As shown in FIG. 4, the power source 33 includes the rechargeable
electricity storage unit 34 and a power receiving unit 35. The
power receiving unit 35 receives energy supply from the outside and
charges the electricity storage unit 34. Examples of the
electricity storage unit 34 include, but not particularly limited
to, an electric double layer capacitor (EDLC) and a lithium ion
secondary battery. Examples of the power receiving unit 35 include
a power generating element that converts energy other than
electromagnetic energy into electrical energy and generates power
and a power receiving element that receives electromagnetic energy
from the outside. Examples of the power generating element include
a solar battery and a vibration power generating element. Examples
of the power receiving element include a non-contact charging power
receiving coil.
The power receiving unit 35 according to the present embodiment
includes a non-contact charging power receiving coil 35a as shown
in FIG. 3, and can receive power supply based on electromagnetic
induction from a power feed unit 45 provided on a surface of the
installation stand 46 in the load port device 40. Power received or
generated by the power receiving unit 35 is stored in the
electricity storage unit 34 and is used by the transmitter 32 to
transmit and receive information and by the detector 31 to detect
the atmosphere in the FOUP 20.
The communication controller 36 shown in FIG. 4 controls power
supply from the power source 33 to the transmitter 32. For example,
the communication controller 36 can cut off power supply from the
power source 33 to the transmitter 32 in a non-communication period
where the transmitter 32 does not communicate information. It is
thus possible to reduce power consumed to keep the transmitter 32
in a standby state (sleep state) and effectively use power from the
power source 33.
The communication controller 36 can control the transmitter 32 to
wirelessly transmit the second information different from the first
information on a detection result of the atmosphere to the receiver
44 of the load port device 40 when a voltage of the electricity
storage unit 34 becomes a predetermined value or more. With this
configuration, even if a voltage of the electricity storage unit 34
in the measurement device 30 becomes less than a predetermined
value while the measurement device 30 is transported together with
the FOUP 20, the measurement device 30 can operate when the voltage
of the electricity storage unit 34 recovers to a predetermined
value or more by charging the electricity storage unit 34 via the
power receiving unit 35. That is, if a voltage of the electricity
storage unit 34 recovers to a predetermined value or more, the load
port device 40 can recognize that the measurement device 30 of
interest is in a state capable of communication and detection
operation based on reception of the second information composed of
an acknowledgment request signal or so by the receiver 44 of the
load port device 40. Thus, even if the transmitter 32 of the
measurement device 30 is not always maintained in the standby state
capable of signal transmission and reception, the load port device
40 can operate the measurement device 30 and obtain a detection
result of the atmosphere in the FOUP 20 by transmitting a control
signal to the measurement device 30 via the receiver 44 after
reception of the second information.
Incidentally, the communication controller 36 controls not only
power supply from the power source 33 to the transmitter 32 but
also power supply from the power source 33 to the detector 31 and
the operation of the transmitter 2 and the detector 31. For
example, the communication controller 36 is composed of a
microcontroller (MCU), but is composed of any configuration.
As shown in FIG. 3, the measurement device 30 includes the cover
portion 38. The cover portion 38 covers the detector 31 excluding
the sensing portion 31a in contact with the atmosphere in the FOUP
20, the transmitter 32, and the power source 33 so as to avoid
contact with the atmosphere in the FOUP 20. The measurement device
30 including the cover portion 38 can protect circuits, electronic
parts, and the like constituting the detector 31, the transmitter
32, and the power source 33 from outgas or so from the wafer 10,
and has preferable reliability.
FIG. 5 is a schematic perspective view showing a vicinity of the
installation stand 46 of the load port device 40. FIG. 6 is a
conceptual view for explaining a communication state between the
measurement device 30 and the load port device 40. As shown in FIG.
5 and FIG. 6, the load port device 40 includes the power feed unit
45 arranged on an upper surface of the installation stand 46. As
shown in FIG. 5, the power feed unit 45 includes a non-contact
charging power feeding coil 45a. The power feeding coil 45a is
arranged to face the power receiving coil 35a (see FIG. 3) of the
measurement device 30 while the FOUP 20 is mounted on the
installation stand 46. The power feeding coil 45a can supply power
to the power receiving coil 35a by electromagnetic induction.
As shown in FIG. 6, the receiver 44 of the load port device 40
wirelessly communicates the first information on a detection result
of the atmosphere in the FOUP 20, the second information associated
with the voltage of the electricity storage unit 34, any other
control information, and the like with the transmitter 32 provided
in the measurement device 30 of the FOUP 20. The radio frequency
used for communication between the receiver 44 and the transmitter
32 is not limited, and may be in the 2.4 GHz band that is used by
Wi-Fi and Bluetooth.RTM. or in a sub-GHz band (the 920 MHz band)
longer in communication range than the 2.4 GHz band.
As shown in FIG. 6, the receiver 44 of the load port device 40
receives the first information on a detection result of the
atmosphere in the FOUP 20 from the measurement device 30 arranged
in the FOUP 20, and the controller 43 of the load port device 40
controls a cleaning gas inlet like the front purge nozzle 41 and
the bottom purge nozzle 42 shown in FIG. 1 based on the detection
result. This allows efficient and appropriate cleaning of the
interior of the FOUP 20. The detection result of the atmosphere in
the FOUP 20 measured by the measurement device 30 may be sent to a
HOST computer 80 in the factory directly or via the receiver 44.
The HOST computer 80 may calculate a requirement for cleanliness in
the FOUP 20 by calculating the correlation between a parameter
associated with the quality of the wafer 10 and the detection
result of the atmosphere in the FOUP 20 and use the requirement as
a threshold used at the time of starting or ending cleaning
processing on the FOUP 20.
FIG. 11 is a flowchart representing a FOUP 20 interior cleaning
process to be performed in the load port device 40 and the FOUP 20
provided with the measurement device 30 shown in FIG. 1. In step
S001 shown in FIG. 11, the controller 43 of the load port device 40
detects that the FOUP 20 has been correctly mounted on the
installation stand 46. In step S002 shown in FIG. 11, the
controller 43 of the load port device 40 drives the power feed unit
45 provided on the upper surface of the installation stand 46 and
feeds power to the power receiving unit 35 (see FIG. 4) of the
measurement device 30 provided in the FOUP 20. With the power
feeding, the electricity storage unit 34 (see FIG. 4) in the
measurement device 30 is charged, and the voltage of the
electricity storage unit 34 rises.
In step S003 shown in FIG. 11, the communication controller 36 of
the measurement device 30 provided in the FOUP 20 controls the
transmitter 32 and transmits the second information sent when a
voltage of the electricity storage unit 34 recovers to a
predetermined value or more to the receiver 44 of the load port
device 40. When the receiver 44 of the load port device 40 receives
the second information, the controller 43 of the load port device
40 recognizes that the measurement device 30 is in an operable
state.
In step S004 shown in FIG. 11, the measurement device 30 starts
detection of the atmosphere in the FOUP 20. More specifically, the
load port device 40 after reception of the second information
indicating that the measurement device 30 is in the operable state
transmits a control signal instructing the measurement device 30 to
start an operation of detecting the atmosphere in the FOUP 20 to
the transmitter 32 of the measurement device 30 via the receiver
44. The measurement device 30 after reception of the control signal
via the transmitter 32 brings the detector 31 into operation and
detects the atmosphere in the FOUP 20. In addition, the transmitter
32 of the measurement device 30 wirelessly transmits the first
information including a detection result by the detector 31 to the
receiver 44 of the load port device 40.
In step S005 shown in FIG. 11, the receiver 44 of the load port
device 40 receives the first information transmitted by the
transmitter 32 of the measurement device 30. In step S006 shown in
FIG. 11, the controller 43 of the load port device 40 controls the
front purge nozzle 41 and the bottom purge nozzle 42 and starts
cleaning of the interior of the FOUP 20. In this case, the
controller 43 of the load port device 40 may change cleaning
operation on the FOUP 20 based on the detection result included in
the first information received by the receiver 44. For example, if
the controller 43 of the load port device 40 recognizes from the
first information that the cleanliness of the FOUP 20 is not less
than a predetermined value or more, the controller 43 may end the
series of processes shown in FIG. 11 without performing the
cleaning operation.
If the controller 43 recognizes from the first information that the
cleanliness of the FOUP 20 is less than a predetermined value, the
controller 43 of the load port device 40 introduces cleaning gas
into the FOUP 20 using the front purge nozzle 41 and starts
cleaning processing on the interior of the FOUP 20 as shown in FIG.
7. Incidentally, a process of opening the lid 26 of the FOUP 20 and
causing the interior of the FOUP 20 to communicate with the wafer
transport chamber 66 by the load port device 40 may be performed in
parallel between step S002 and step S005 in FIG. 11, or may be
performed after a decision is made in step S006 to perform cleaning
operation.
Even while cleaning gas is introduced into the FOUP 20 via the
front purge nozzle 41 as shown in FIG. 7, the measurement device 30
detects the cleanliness of the FOUP 20 automatically or based on a
control signal from the load port device 40 and transmits the first
information including a detection result of the load port device
40. At this time, the controller 43 of the load port device 40 can
bring the power feed unit 45 into operation and supply power to the
measurement device 30 as needed.
As Shown in FIG. 7, while the cleaning operation on the FOUP 20 by
the front purge nozzle 41 is performed, cleaning gas is introduced
from central and upper regions in the main opening 22a into the
FOUP 20, and an airflow discharged from a lower portion of the main
opening 22a is formed. Since the measurement device 30 is arranged
at the lower portion of the main opening 22a, where gas is
discharged, cleaning gas is prevented from being emitted directly
to the measurement device 30, and the problem of discrepancy
between a detection value from the detector 31 of the measurement
device 30 and an actual atmosphere in the FOUP 20 can be
prevented.
In step S007 shown in FIG. 11, the receiver 44 of the load port
device 40 receives the first information including a detection
result of the cleanliness in the FOUP 20 during the cleaning
operation. The controller 43 of the load port device 40 judges
whether to continue or end the cleaning operation on the FOUP 20
based on the detection result included in the first information
received by the receiver 44.
That is, if the controller 43 of the load port device 40 recognizes
that the cleanliness of the FOUP 20 is less than a predetermined
value based on the detection result included in the first
information received in step S007, the controller 43 continues the
cleaning operation shown in FIG. 7. On the other hand, if the
controller 43 of the load port device 40 recognizes that the
cleanliness of the FOUP 20 is a predetermined value or more based
on the detection result included in the first information received
in step S007, the flow advances to step S008, and the series of
operations are ended.
As described above, since the load port device 40 can recognize a
detection result of the atmosphere in the FOUP 20 in the cleaning
process as shown in FIG. 11, an appropriate and efficient cleaning
processing can be performed on the FOUP 20. In addition, since the
measurement device 30 provided in the FOUP 20 detects the
atmosphere, the atmosphere in the FOUP 20 can be easily and
accurately recognized without leading gas in the FOUP 20 outside.
In addition, since a detection result by the measurement device 30
is transmitted to the load port device 40 through wireless
communication, an electrical contact or the like for data
transmission need not be provided on a surface of the FOUP 20, and
installation of the measurement device 30 in the FOUP 20 little
impairs the airtightness and durability of the FOUP 20.
The measurement device 30 includes the non-contact charging power
receiving coil 35a, which charges the electricity storage unit 34,
and the electricity storage unit 34 of the measurement device 30
can be charged via the power feed unit 45 (the power feeding coil
45a) provided on the installation stand 46 of the load port device
40. Thus, the measurement device 30 with the above-mentioned
configuration can save much trouble in battery life management and
reduce battery management and replacement costs.
The present invention is described above with reference to the
embodiment, but is not limited to the embodiment, and needless to
say, includes many other embodiments, modifications, and the like.
For example, a wafer transport container for transporting the wafer
10 is not limited to the FOUP 20, and the measurement device 30 may
be provided in a different container, such as a FOUP for
transporting the wafer 10. For example, a wafer transport container
interior cleaning device that is provided with the receiver 44 as
shown in FIG. 6 and cleans the interior of the FOUP 20 using the
first information from the measurement device 30 is not limited to
the load port device 40 shown in the embodiment, and may be a
special purpose machine for cleaning the interior of the FOUP 20 (a
so-called standalone wafer transport container interior cleaning
device), or a stocker for the FOUP 20, or the like. The measurement
device 30 may detect not only the atmosphere of the FOUP 20
installed in a wafer transport container interior cleaning device
but also the atmosphere of the FOUP 20 in a location other than a
wafer transport container interior cleaning device, such as a
buffer station. In this case, the first information including a
detection result is sent from the transmitter 32 as a slave unit to
the load port device 40 including the receiver 44 as a master unit
or the HOST computer 80. For example, in the cleaning process in
the load port device 40, cleaning processing using the bottom purge
nozzles 42a and 42b as shown in FIG. 8 can be performed instead of
cleaning processing using the front purge nozzle 41 as shown in
FIG. 7.
In the cleaning processing using the introduction nozzles 42a and
the discharge nozzles 42b as shown in FIG. 8, cleaning gas is
introduced into the FOUP 20 through the bottom openings 23a, and
gas in the FOUP 20 is discharged through the bottom openings 23b.
Since the detector 31 of the measurement device 30 is provided in
the vicinity of the bottom openings 23b, where the discharge nozzle
42b is connected, that is, since the detector 31 of the measurement
device 30 is provided in a region of the bottom portion 22b closer
to the main opening 22a than the central position in the FOUP 20,
the measurement device 30 can accurately detect the atmosphere in
the FOUP 20.
FIG. 9 is a conceptual view representing an example of cleaning
processing to be performed using a FOUP 120 and a load port device
140 according to a first modification. The example shown in FIG. 9
is different from the example shown in FIG. 8 in that a discharge
nozzle that discharges gas in the FOUP 120 is connected to bottom
openings 123a provided at positions farther away from a main
opening 122a than a central position of a bottom portion 122b. In
the example shown in FIG. 9, an introduction nozzle that introduces
cleaning gas into the FOUP 120 is connected to bottom openings 123b
provided at positions closer to the main opening 122a than the
central position of the bottom portion 122b.
Since the detector 31 of the measurement device 30 is provided in
the vicinity of the bottom openings 123a, where the discharge
nozzle is connected, that is, since the detector 31 of the
measurement device 30 is provided in a region of the bottom portion
122b farther away from the main opening 122a than the central
position in the FOUP 120, the measurement device 30 can accurately
detect an atmosphere in the FOUP 120.
FIG. 10 is a conceptual view representing an example of cleaning
processing to be performed using a FOUP 220 and a load port device
240 according to a second modification. In the example shown in
FIG. 10, cleaning gas is introduced into the FOUP 220 via an
introduction nozzle 286 provided in the FOUP 220, and gas in the
FOUP 220 is discharged via a main opening 222a and bottom openings
223b close to the main opening 222a. In the example shown in FIG.
10, the measurement device 30 is preferably arranged in the
vicinity of the main opening 222a or the bottom openings 223b, more
preferably in a bottom portion 222b between the main opening 222a
and the bottom openings 223b.
In each of the measurement devices 30 illustrated in the embodiment
and the modifications described above, the detector 31, the
transmitter 32, the power source 33, the communication controller
36, and the cover portion 38 are integrated as shown in FIG. 3, but
a measurement device is not limited thereto. In another embodiment,
the detector 31 and the power source 33 may be arranged at separate
locations in the FOUP 20. For example, the detector 31 may be
arranged on a ceiling surface of the FOUP 20, and the power source
33 may be arranged on the bottom portion 22b. Incidentally, the
power receiving coil 35a shown in FIG. 3 is preferably provided on
the bottom portion 22b of the FOUR 20, and the power feeding coil
45a shown in FIG. 5 is preferably provided on the installation
stand 46. This makes it possible to reduce a distance between the
power receiving coil 35a and the power feeding coil 45a, and the
power efficiency at the time of charging can be thereby
enhanced.
NUMERICAL REFERENCES
10 . . . wafer 20 . . . FOUP 22 . . . housing portion 22a . . .
main opening 22b . . . bottom portion 23a, 23b . . . bottom opening
26 . . . lid 30 . . . wafer transport container interior atmosphere
measurement device (measurement device) 31 . . . detector 31a . . .
sensing portion 32 . . . transmitter 33 . . . power source 34 . . .
electricity storage unit 35 . . . power receiving unit 35a . . .
power receiving coil 36 . . . communication controller 38 . . .
cover portion 40 . . . load port device 41 . . . front purge nozzle
42 . . . bottom purge nozzle 42a . . . introduction nozzle 42b . .
. discharge nozzle 43 . . . controller 44 . . . receiver 45 . . .
power feed unit 45a . . . power feeding coil 46 . . . installation
stand 47 . . . door 60 . . . EFEM 62 . . . transport robot 64 . . .
wall portion 80 . . . HOST computer
* * * * *